<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
</body>
</html>

<script>
    var year = prompt("年")
    if ((year % 4 == 0 & year % 100 != 0) || (year % 400 == 0)) {
		alert("该"+year+"为闰年")
	}else{
        alert("该"+year+"为平年")
    }
</script>